1. Field of the Invention
This invention relates in general to materials spreading devices and more particularly to a manually manipulatable mechanism for applying a layer of crushed rocks in selected areas of a pavement surface.
2. Description of the Prior Art
In the art of highway maintenance, it is a common practice to periodically renew the surface of the pavement by applying what is referred to as a chip seal coat on the existing paved surface. After repair of damaged areas, such as the filling of cracks and chuck holes, a seal coating of asphalt in liquid form is sprayed on the entire paved surface and a coating of crushed rocks, referred to in the industry as chips, is spread on the asphalt while it is still in the uncured state. The surface is then rolled with a special roller vehicle, which embeds the chips in the asphalt seal coating.
The equipment used in this type of highway maintenance is very large and expensive to operate. For example, a chip spreader vehicle which is commonly used in relatively large maintenance projects is a highly specialized automotive vehicle having a chip receiving bin on its back end, a chip dispensing hopper with a power driven auger therein on its front end, and a conveyor system for conveying the chips from the receiving bin to the dispensing hopper. A conventional dump truck is backed up so that its tail gate end is adjacent the chip receiving bin of the chip spreading vehicle, and its dump bed is raised to deliver the chips at a controllable delivery rate into the chip receiving bin. The dump truck is connected to the chip spreading vehicle and is towed by the vehicle as it is operated to accomplish its chip spreading task. This type of highly specialized vehicle is very expensive both from its initial cost and operating cost standpoints and its use is usually reserved for relatively large jobs.
Another type of chip spreader mechanism in common usage is sometimes referred to as a tail gate spreader in that it is mounted on the back of a dump truck to convert it into a special usage machine.
In both of the above described mechanisms, the intended usage thereof is to spread a layer of chips on large areas of the paved surface and the use of either one of those prior art machines cannot be economically justified for spot repair work, such as chuck hole repairing, shoulder work, and the like. For this reason, chuck hole repair work, for example, is usually accomplished by first cleaning out the hole then filling it with an asphalt-aggregate mix, leveling it by hand and finishing the repair by rolling it with a hand operated roller. Since no equipment for applying an asphalt seal coating and applying a chip coating is available, or suitable, for such spot repair work, the chip-seal coating is simply omitted. In the absence of such a coating, the repaired areas are subject to relatively rapid deterioration due to traffic and environmental damage.
To the best of our knowledge, no equipment has been devised or suggested which is suitable for use in applying a layer of crushed rocks, or chips, in relatively small areas where spot repair work is being accomplished on paved surfaces. Therefore, a need exists for a manually manipulatable mechanism for applying a layer of crushed rocks on selected areas of a paved surface.